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 ###Instrução: Qual é a soma do Solidat (c) cujo propósito é exibir tipo, trabalhos pesados e uma dureza (brinell) menor que 33?
 ###Tabelas: CREATE TABLE alloys_for_mechanical_composition (alloys_for_mechanical_composition_id AUTO_INCREMENT PRIMARY KEY, Sn/Sb (%) VARCHAR, Liquidat (°C) INT, Solidat (°C) INT, Hardness ( Brinell ) INT, Purpose VARCHAR) CREATE TABLE arizona (arizona_id AUTO_INCREMENT PRIMARY KEY, District VARCHAR, Incumbent VARCHAR, Party VARCHAR, First elected INT, Results VARCHAR) CREATE TABLE list_of_oldest_sitting_mps_since_1945 (list_of_oldest_sitting_mps_since_1945_id AUTO_INCREMENT PRIMARY KEY, Born VARCHAR, Became oldest MP VARCHAR, Left House VARCHAR, Age on leaving VARCHAR, Died VARCHAR, Political Party VARCHAR) CREATE TABLE list_of_recent_northumberland_cup_winners (list_of_recent_northumberland_cup_winners_id AUTO_INCREMENT PRIMARY KEY, Season VARCHAR, Northumberland Senior Cup VARCHAR, Northumberland Senior Benevolent Bowl VARCHAR, Northumberland Minor Cup VARCHAR, Northumberland Women's Cup VARCHAR) CREATE TABLE medallists_by_nation (medallists_by_nation_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Nation VARCHAR, Gold INT, Silver INT, Bronze INT, Total INT)  
SELECT SUM Solidat (°C) FROM alloys_for_mechanical_composition WHERE Purpose = display type, heavy duty jobs AND Hardness ( Brinell ) < 33